Clinical Trial Registration and News
As the average childbearing age steadily increases, more and more fetal health risks are associated with advanced maternal age. But what risks, if any, are linked to fathers who are older at the time of conception?
New research suggests that advanced paternal age may contribute to higher rates of mental health issues and educational deficits in children. The findings stem from a collaborative study between Indiana University and Stokholm’s Karolinska Institute.
After studying an expansive set of data that encompassed every birth in Sweden from 1973 to 2001, researchers found stark differences between the children born to younger fathers versus older ones. When compared to the offspring of a 24-year-old father, a child born to a 45-year-old father was found to be 13 times more likely to develop ADHD. These children were also over three times more likely to have autism and twice as likely to have a psychotic disorder. Researchers also reported that children of older fathers were 25 times more likely to develop bipolar disorder.
Suicide risk was significantly higher among this group, as well.
“The main finding from our study is that the associations between advancing paternal age at childbearing and offspring psychiatric and academic problems were larger than in previous studies,” said lead author Brian D’Onofrio, associate professor in the Department of Psychological and Brain Sciences at Indiana University Bloomington.
According to D’Onofrio and his team, the risk of developing these mental health problems gradually increased with paternal age. Researchers were surprised when they conducted more advanced analyses that compared the rates of these problems among siblings.
“We compared offspring born when a father was younger to their siblings when the father was older,” said D’Onofrio. “We did not expect that the magnitude of the associations between advancing paternal age at childbearing and offspring problems would be larger.”
Researchers say sperm replication might be at play since genetic mutations are more likely to be present in the sperm of older men.
“The results are consistent with molecular genetic research that links advancing paternal age at childbearing to more genetic mutations in their sperm,” said D’Onofrio. “But there could be other explanations, as well”.
By Marianne Hayes